Robber flies such as this species with the scientific name Promachus hinei are to other insects what falcons are to other birds: swift predators on the wing.
These predators can be recognized by their usually bearded face and a concave top of the head between the eyes. This is a large robber fly which is approximately 2-4 cm in length. Females are larger than males. They act like flycatchers, perching on logs, leaves, twigs, or the ground, cocking their heads at insects passing overhead, and dashing out to apprehend a victim.
You might hear this species before you see it, as it departs its perch with a loud, buzzing flight, quickly landing again nearby, usually on a vertical branch or twig.